With respect to 1,2,3,4-tetrahydro-2,4-dioxoquinazoline derivatives having a 1-(6,7-dimethoxy-4-quinazolinyl)-4-piperidinyl group at the 3-position, those having a hydrogen atom, a chlorine atom or a nitro group at the 6-position are described in Chem. Pharm. Bull., 38, 1591-1595 (1990). Further, it is known that a compound having adenosine uptake inhibitory activity exhibits myocardium protecting activity [Circul., 80 1400-1411 (1989); Am. J. Physiol., H1 570-1577 (1991); J. Cardiovasc. Pharmacol., 20, 173-178 (1992)].